Linear surgical staplers are well known in the prior art. Typical examples of such devices are described in WO 00/53102, U.S. Pat. No. 5,772,099, U.S. Pat. No. 5,676,674, U.S. Pat. No. 5,389,098, and U.S. Pat. No. 6,872,214. All of these devices comprise a staple cartridge in which is stored one or more arrays of staples. The essentially U-shaped staples are stored with their legs aligned with and pointing in the direction of slots in the face of the cartridge. The staples actively forced to move through the slots when the firing mechanism is activated. The firing mechanism comprises some form of sliding cam or wedge positioned so that it can be moved longitudinally under the staples. When caused to move the wedge slides under the staple and either directly or with the aid of a staple pusher forces the staple to move in the direction of the slot until the staple is eventually forced completely out of the cartridge. The mechanical arrangement of the cams, etc. is of varying degrees of complexity, but in all cases is not simple and requires complex manufacturing and assembly methods and unnecessary expense all of which could be reduced if a simpler stapler firing method could be devised.
A frequent surgical procedure that has to be performed by surgeons is the closure of holes that exist in biological tissue. These holes can be either the result of injury or created by the surgeon to gain access to internal parts of the body on which he must operate.
Traditional methods of closure of the holes are stitching using a needle and natural or artificial thread, gluing the edges of the hole together, or fastening with one of many different forms of surgical fastener of staple. A hole on the outer surface of the body, e.g. a bullet hole or an incision cut into the outer surface of the abdominal wall for insertion of a laparoscope, is visible, easy to access, and easy to close. When the hole is in the wall of an internal organ, e.g. the wall of the stomach, the closure is much more complex. In this case, either major surgery is performed to open the body and gain access to the site of the hole, or laparoscopic or endoscopic devices and techniques can be employed. To perform the closure procedure laparoscopically or endoscopically there must be provided visualization means in order to be able to view the hole and control the operation of the various instruments used to close it, grabbing means to pull and hold the edges of the hole together, and fastening means to attach the edges of the tissue together thereby closing the hole. Introducing and manipulating the instruments and accessories into the body of the patient requires a great deal of skill and the cooperative action of a team of trained personnel.
It is a purpose of the present invention to provide an endoscopic stapler device that comprises a simpler mechanism for firing the staples from the cartridge than that which exists in the prior art.
It is another purpose of the present invention to provide an endoscopic stapler device that comprises all the features necessary for a surgeon to locate and close a hole in the tissue of an internal organ.
Further purposes and advantages of this invention will appear as the description proceeds.